Object of the invention
[0001] The present patent application concerns, firstly, an improved bolt suitable to be
tightly inserted into a respective opening or space provided in a vehicle battery
housing lid, where one or more such bolts serve to fix an external component, such
as a contactor, on or to the upper surface of the lid, and where the bolt incorporates
remarkable innovations and advantages with respect to the bolts known today.
[0002] Secondly, this invention relates to a system for fixing the bolt to a vehicle battery
housing lid, wherein the system includes at least: a bolt suitable to be inserted,
in a close-fitting manner, in a passage provided in a battery housing lid, and means
for fastening the upper surface of the head of the bolt, corresponding to the surface
that is closest to the bolt's elongate body, to a lower surface of the lid.
Background of the invention
[0003] Today the batteries for electric, hybrid or any type of hydrogen-fuelled vehicles
are comprised of different elements, which are arranged inside an essentially hollow
housing which is closed at the top by a top lid. Said housing plus lid assembly, which
must necessarily be fully airtight, is referred to in the jargon as a battery box
or casing.
[0004] The battery lids suitable for a vehicle to which this invention refers are manufactured
from a rigid, thin sheet, generally of metal, with an essentially flat configuration,
although it may be ridged and contoured, for example, rectangular, although its configuration
may vary depending on the battery model in question.
[0005] A current common manufacturing process for such a battery lid is by stamping.
[0006] The covers may additionally have one or more openings or through holes arranged in
specific positions on their lower surface, so that associated external parts can pass
through and/or be inserted into the same and be fixed by means of fasteners in the
cover, and they may have different spatial shapes: flat, and concave or convex in
different positions.
[0007] In particular, some models of battery lid incorporate an opening for fitting an external
component, which is an external part of the battery and in the vicinity of said opening
one or more apertures are provided to permit the insertion of a respective fixing
bolt in each aperture. Said external component is securely mounted on the upper surface
of the battery lid by means of one or more fixing bolts. This external component may
be, for example, a contactor, which is an electrical element, securely accessible
from the outside, and whose function is to connect the battery to the electrical system
of a vehicle. Said contactor is securely mounted on the upper surface of the battery
lid protruding from the upper portion of said lid.
[0008] Additionally, some models of lids may have a perimeter edge with a number of holes
distributed along the perimeter edge, wherein said holes are configured to fix said
lid to the battery housing.
[0009] The present invention focuses on the models of battery lids that incorporate, at
least, an opening for placing a contactor, where said contactor is placed partially
or totally inserted in said opening, where part of the contactor may be in contact
with the upper surface of the lid when it is in position. The contactor is fixed to
the upper surface of the lid by means of one or more fixing elements, such as one
or more bolts. By way of example, four identical bolts may be provided in the vicinity
of the opening where the contactor is located, and wherein each bolt is configured
to be inserted, in a close-fitting manner, into a respective hole in the lid intended
for such purpose.
[0010] The external component must necessarily be mounted on the bolt from above. Therefore,
it is necessary to provide a respective hole in the battery lid to receive the head
of the bolt, since the head of each bolt is arranged resting on and flush against
the lower surface of the battery lid. If the bolt head were placed on the upper face
of the lid then a risk would be generated for the airtightness at that point, which
presents a serious problem, since there are very high airtightness requirements for
the entire battery lid.
[0011] The bolts known today that are suitable for this type of assembly with a very high
degree of airtightness in battery lid have the following parts:
- an elongate body extending in a longitudinal direction, which is threaded on its external
surface, configured to take a nut which, in turn, fixes a contactor of the battery,
and where, in its mounted position, it is located on the side corresponding to the
upper face of the lid, and
- a head, at one end of the body, configured to be arranged in the mounting position
abutting against the underside of the lid.
[0012] This type of bolt is permanently fastened to the lower face of the lid by means of
a fastening medium. The currently known means of attachment are some type of adhesive
and also by welding.
[0013] It has been found that the application of a weld is not an optimal solution for this
type of assembly since it does not guarantee airtightness by itself, and it can cause
perforations and deformations to the sheet of the lid, which also causes undesired
failures in the airtightness.
[0014] Solutions known today which use an adhesive to fix the top of the bolt head to the
bottom face of the lid present a number of drawbacks, such as that the attachment
of the top surface of said bolt head to a surface of the lid is not entirely efficient
and does not provide optimal fixation.
[0015] Moreover, it is sought that when the bolts are placed inside the respective holes
or apertures made in the lid and are adhered or welded they have a power of adhesion/fixation
such that they detach when they receive a strong impact, but remain fixed without
detaching from the lid during its "normal" use or handling. The purpose of this special
feature is to prevent the incorrect installation of bolts, which could lead to poor
installation with a lack of airtightness.
[0016] For the reasons set forth above, there is a need in the market for improving the
bolt for a battery lid as well as providing an assembly to fix the bolt to the battery
lid.
Description of the invention
[0017] The first object of the present invention is to provide a bolt for a lid to a battery
housing, wherein said batteries are preferably used in a vehicle, and wherein the
bolt is suitable to be inserted, in a close-fitting manner, in a passage provided
in the surface of a battery lid and serves to fix an external component on or to the
battery lid, and which solves the aforementioned drawbacks, presenting the advantages
described below.
[0018] In accordance with this first object, the present invention provides a bolt for a
battery lid suitable for a vehicle, wherein the bolt is suitable to be inserted, in
a close-fitting manner, into a hole that passes through the lid, wherein the bolt
has the following known features:
- an elongate body extending in a longitudinal direction and wherein the body comprises
a threaded outer portion, and
- a head arranged at the lower end of the body,
where the bolt is configured to allow the fixing of an external component on or to
the upper surface of the lid, and where the body of the bolt is configured to be inserted,
in a close-fitting manner, into the hole provided in the lid, so that the body of
the bolt protrudes from the upper surface of the lid and the head of the bolt is arranged
on the side of the lower surface of the lid.
[0019] Unlike the bolts already known in the state of the art for the lids to housings containing
batteries preferably those used in vehicles, the bolt of the present invention is
characterised by further having:
- an intermediate portion arranged in the lower part of the body, where the lower part
of the intermediate portion contacts the upper part of the head of the bolt, and where
the outer lateral surface of the intermediate portion is provided with grooves in
its outer lateral surface, configured to contact a part of the inner surface of the
passage through the lid, ensuring its fixing.
[0020] Said plurality of grooves is intended to contact a part of the inner surface of the
passage through the lid, interlocking against the hole provided in the lid, but without
deforming the outer surface of the lid or any other part of the lid in the operation
of exerting a pinning force to position the bolt inside the hole with a tool.
[0021] The bolt proposed by the present invention provides the following advantages:
- Eliminates risks of perforations.
- Guarantees a resistant torque in the joint sufficient to allow the mounting and tightening
of the fixing nuts for the contactors, supports and any auxiliary element that the
vehicle needs.
- Acts as a safety fuse against improper handling or impacts that may partially deteriorate
the joint allowing its use, but without guaranteeing airtightness.
- Connects the lid-bolt assembly by means of relatively low pressure systems and with
easy and safe quality control of the connection.
[0022] As an option, the head may be a widened head, with a greater width than the intermediate
portion, and wherein the head is devoid of grooves in its outer lateral surface.
[0023] Preferably, the sheet constituting the battery lid has a thickness of at least 1.5
mm.
[0024] In particular reference to the intermediate portion of the bolt, it is preferably
arranged at the bottom of the bolt body, continuously attached, i.e. the intermediate
portion is integral to the bolt body. Also preferably, the intermediate portion is
continuously attached, i.e. the intermediate portion is integral to the bolt head.
[0025] Also preferably, the intermediate portion has a slightly greater width than the bolt's
threaded body.
[0026] Also preferably, the bolt head can have a square, rectangular, hexagonal or any other
possible geometric shape.
[0027] Also preferably, the intermediate portion can have a prismatic configuration of square,
rectangular, hexagonal or any other geometric, in addition to cylindrical, shape.
In this case, if the intermediate portion is prismatic, it is not necessary to have
a groove in its outer surface, since the shape of its rectangular, hexagonal, etc.
base ensures the maintenance of the torque for tightening the bolt nut.
[0028] According to a possible embodiment of the invention, the intermediate portion of
the bolt has a height of between 1.5 mm and 3 mm and a width or diameter greater than
the gauge of the bolt.
[0029] According to a possible embodiment of the invention, the plurality of grooves provided
on the outer side surface of the intermediate portion extend regularly in the longitudinal
direction, wherein said longitudinal direction is the axial direction of the bolt
body.
[0030] According to a possible embodiment of the invention, the plurality of grooves provided
on the outer lateral surface of the intermediate portion comprises a plurality of
flutes and peaks alternating in a zigzag shape. Preferably, the plurality of alternating
flutes and peaks have a straight triangular profile. Preferably, the plurality of
grooves occupies the entire outer surface of the grooved portion.
[0031] In particular reference to the widened head of the bolt, it preferably has a thickness
between 1.1 and 2.5 times greater than the gauge of the bolt.
[0032] According to one possible embodiment of the invention, the widened head, in the case
of a metric 6, has a cylindrical body of diameter between 8 mm and 18 mm or even more
than 18 mm.
[0033] With reference to the bolt body in particular, according to a possible embodiment,
the bolt body has a cylindrical or prismatic configuration. Preferably, the body has
a width or diameter between metric 4 and metric 8. Therefore, the enlarged head has
a width or diameter that is nearly twice the width or diameter of the bolt body. Preferably,
the bolt body comprises, in part or in its entirety, a portion of its threaded outer
surface.
[0034] Optionally, between the body and the intermediate portion of the bolt there is a
conical tapering portion. By way of example, this conical tapering portion has a height
between 1.4 mm and 2.4 mm. The function of said conical tapering portion is to allow
the manufacture of the bolt using current manufacturing means. That is, it does not
have any specific technical function for the bolt.
[0035] The second object of the present invention is to provide a fastening system for the
bolt described above in a vehicle battery housing lid, and wherein the system solves
the aforementioned drawbacks, presenting the same advantages as described above for
the bolt.
[0036] According to this second object, the present invention provides a system for fastening
a bolt to a vehicle battery housing lid, wherein the fastening system comprises the
following known features:
- at least one bolt, as defined above as the bolt of the invention, for fixing an external
component on or to the upper face of the surface of the battery housing lid; and
- a medium for fastening the upper surface of the bolt head, corresponding to the surface
which is closest to its elongated body, to a lower surface of the lid.
[0037] The external component to be fixed with one or more bolts on or to the upper face
of the surface of the battery lid can, for example, be a contactor, although it can
be used for fixing any support and/or system that must be attached so that it is securely
mounted on said upper surface, but with the ability to be subsequently manipulated
without deteriorating the behaviour of the bolt-lid assembly.
[0038] Unlike the fastening systems of bolts in battery lids already known in the state
of the art, that of the present invention is characterised, in addition to the novel
features of the bolt set forth above, in that:
- the medium for fastening the upper surface of the head of the bolt to a lower surface
of the lid is an adhesive.
[0039] Advantageously, the function of the adhesive is to adhere the upper surface of the
head to a face or lower surface of the lid with a removal force such that the attachment
is strong enough to maintain the attachment of both parts, but at the same time not
too strong, thereby serving as a safety fuse in case of blows or bad handling. In
addition, it provides the advantage of ensuring the airtightness of the joint.
[0040] According to a preferred embodiment of the invention, the adhesive is arranged on
the entire lateral outer surface of the intermediate portion and also on at least
half of the upper surface of the head corresponding to the half closest to the grooved
portion.
[0041] Preferably, the adhesive used is a water-based adhesive or a toluene-based microencapsulated
adhesive.
[0042] The applicant of the present invention has carried out tests to verify the improved
properties of the adhesive with respect to other types of adhesives known in the state
of the art. Specifically, a lid with an opening and four holes located in the vicinity
of its perimeter edge has been tested by inserting respective bolts and attaching
them to said lid by two types of adhesive.
[0043] The results of said tests show that the adhesive used in the present invention results
in a removal force over the 4 bolts that is 30% to 50%, or even more, times greated
than if the adhesives known in the prior art are used.
[0044] For a better understanding of the description made herein, a set of drawings has
been provided wherein, schematically and solely by way of a non-limiting example,
practical examples are represented of examples of the fastening bolt for battery housing
lids and the system for fastening said bolt to the lid, which are the subject of the
present invention.
Brief description of the drawings
[0045]
Figure 1 is a perspective view of an example of a battery housing with a lid for a
vehicle, wherein a connector is securely mounted on the top of the lid by four fixing
bolts according to the present invention.
Figure 2 is a top plan view of an example of the example battery housing lid for a
vehicle shown in Figure 1.
Figure 3 is the same top perspective view as the previous Figure 2, but with the four
fixing bolts placed in their mounting position.
Figure 4 is a front elevation view of Figure 3 with the four fixing bolts positioned
in their mounting position.
Figure 5 is a sectional view of a detail A of Figure 4 where a fixing bolt placed
in its mounting position can be seen.
Figure 6 is a front elevation view of a possible embodiment of the fixing bolt according
to the present invention.
Figure 7 is a cross-sectional view B-B with reference to Figure 6.
Figure 8 is a view of a detail C from Figure 6 corresponding to a lower part of the
bolt, wherein the adhesive layer is represented.
Description of some examples of the embodiment of the invention
[0046] A preferred embodiment of a battery housing lid (1) suitable for a vehicle that is
the object of the present invention, with four fixing bolts (15) for an external component,
in this case a contactor (25), is described below, with reference to Figures 1 to
7.
[0047] The outer casing of a battery for a vehicle comprises a housing (26) and a lid (1),
where the housing (26) is formed by a receptacle, which defines a cavity suitable
for housing different components of the battery, and the lid (1) is arranged to cover
the access opening to the cavity defined by the receptacle of the housing (26).
[0048] The vehicle battery lid (1) is formed by a rectangular-shaped sheet extending in
the X-Y plane and has a low thickness or height. In the vicinity of the peripheral
edge (24) of said lid (1) there are provided a number of holes (5) distributed along
said peripheral edge. As can be seen in Figures 2 and 3, the upper surface (3) of
the lid (1) has a series of ridges (21) and a rectangular-shaped opening (14) for
locating a contactor (25). In particular, the opening (14) has in the vicinity of
its four vertices four holes or inlets (6) for receiving four respective bolts (15).
[0049] In Figure 2 below, only the battery lid (1) can be seen, without the contactor (25).
Therefore, it is possible to see the through opening (14), which has a substantially
rectangular perimeter, and, in the vicinity of its perimeter edge, 4 holes (6) are
present.
[0050] Each bolt (15) is mounted below the lid (1) in each of these holes (6), so that the
body (16) of each bolt (15) protrudes outwards beyond the outer surface (3) of the
lid (1), see Figures 3 and 4.
[0051] Figures 3 to 5 show the mounted assembly of the battery lid (1) and four fixing bolts
(15) inserted in a respective hole or space (6) provided in said surface (2) of the
housing lid (1). Figures 4 and 5 show how the lower surface (17b) of the head (17)
of the bolt is flush abutting against the lower surface (4) of the lid (1) and the
body (16) of the bolt (15) protrudes on the other side, the upper side, of the lid
(1). The intermediate portion (18) is inserted in the mounting position inside the
hole or inlet (6) provided in the sheet (2) of the lid (1).
[0052] A possible embodiment of the fixing bolt (15) of the present invention is illustrated
in Figures 6 to 8, wherein the adhesive layer (20) is also illustrated.
[0053] The fixing bolt (15) is formed by an elongate body (16), of cylindrical configuration,
extending in a longitudinal direction corresponding to the longitudinal axis of the
bolt body and having part or all of its outer surface threaded. Arranged at the lower
end of the body (16) is an enlarged head (17), in this case with a circular contour,
with a smooth outer surface. Furthermore, the bolt (15) has an intermediate portion
(18), of cylindrical configuration, arranged at the bottom of the body (16), wherein
the grooves extend over the entire lateral surface of the intermediate portion (18)
in longitudinal direction in a zigzag manner with a right triangular cross-section,
see Figures 6 and 7. A conical tapering portion (19) is formed between the body (16)
of the fixing bolt (15) and the enlarged head (17).
[0054] Figures 7 and 8 show the adhesive layer (20) arranged on most of the outer surface
of the intermediate portion (18) and also on part of the upper surface (17a) of the
head (17) corresponding to the area closest to the intermediate portion (18). Figure
7 shows only the horizontal area of the adhesive layer (13) arranged on the upper
surface (17a) of the head (17) of the bolt (15).
[0055] The bolt has an intermediate portion (18) with an outer diameter such as to be inserted
in a close-fitting manner inside the hole (6).
[0056] Although reference has been made to a specific embodiment of the invention, it is
evident to a person skilled in the art that the bolts for the lid to the housing for
a battery to be installed in a vehicle described herein is susceptible to numerous
variations and modifications, and that all the aforementioned details can be replaced
by other technically equivalent details, without departing from the scope of protection
defined by the attached claims.
1. Bolt (15) for vehicle battery housing lids (1), wherein the bolt (15) is suitable
to be inserted, in a close-fitting manner, into a hole (6) that passes through the
battery housing lid (1), wherein the bolt (15) has:
- an elongate body (16) extending in a longitudinal direction and wherein the body
(16) has a threaded outer portion, and
- a head (17) arranged at a lower end of the body (16),
where the bolt (15) is configured to allow the fixing of an external component (22)
on or to the upper surface (3) of the lid (1), and where the body (16) is configured
to be inserted, in a close-fitting manner, into the hole (6) in the lid (1), so that
the body (16) of the bolt (15) protrudes from the side of the upper surface (3) of
the lid (1) and the head (17) of the bolt (15) is on the other side of the lid (1);
characterised in that the bolt (15) further has:
- an intermediate portion (18) arranged in the lower part of the body (16), where
the lower part of the intermediate portion (18) contacts the upper part of the head
(17) of the bolt, and where the outer lateral surface of the intermediate portion
(18) is provided with grooves in its outer lateral surface and is configured to contact
a part of the inner surface of the passage through the lid (1).
2. Bolt (15) according to claim 1, wherein the intermediate portion (18) has a greater
width than the threaded body (16).
3. Bolt (15) according to any one of the preceding claims, wherein the intermediate portion
(18) has a cylindrical or prismatic configuration.
4. Bolt (15) according to any one of the preceding claims, wherein the intermediate portion
(18) has a height of between 0.5 mm and 3mm.
5. Bolt (15) according to any one of the preceding claims, wherein the plurality of grooves
provided on the outer side surface of the intermediate portion (18) extend along the
longitudinal direction.
6. Bolt (15), according to claim 5, wherein the plurality of grooves along the intermediate
portion (18) comprise a plurality of flutes and peaks that are alternating in a zigzag
manner.
7. Bolt (15), according to any one of the preceding claims, wherein the widened head
(17) has a diameter of between 8 mm and 18 mm.
8. System for fixing a bolt (15, 20) to a vehicle battery housing lid (1), wherein the
system includes:
- at least one bolt (15) defined in any one of claims 1 to 8, for fixing an external
component on or to the upper face (3) of the surface (2) of the battery housing lid
(1); and
- a medium for fastening (20) the upper surface of the head (3) of the bolt (15) corresponding
to the surface that is closest to the elongate body (2) to a lower surface (4) of
the lid (1);
characterised in that:
- the medium for fastening (20) is an adhesive.
9. System for fastening a bolt (15, 20) according to claim 8, wherein the adhesive (20)
is a water-based adhesive.
10. System for fastening a bolt (15, 20) according to claim 8, wherein the adhesive (20)
is a toluene-based microencapsulated adhesive.
11. System for fastening a bolt (15, 20) according to any one of claims 8 to 10, wherein
the adhesive (20) is arranged on the entire outer lateral surface of the intermediate
portion (18) and also on at least half of the upper surface of the head (17) corresponding
to the half closest to the intermediate portion (18).